Insulator for antenne



f' line: ofi Figure l.;

"Patented Feb. 15,1927.r

i,617,9s9 PATENT oFFrcr..

" 'AMQSFLQYD CUN-mena .or Mmes-1R; COLORADO;

INsULAToR FOR ANTENNE.

Application filed March 13, `1925. Serial No. 15,296.

5. r"Ihisinventionrelates to electrical insu- 1latorsand particularly to an insulator of time.'v suspension .type which is especially adapted to. the support of vantenna wiresfor theftransmissien and reception of radiant ener Y .t

The-object of .the invention 1s to produce anlinsuilator which interposes an extended ydielectric surfacebetween the antenna wire andthe suspensien mean-s; which provides fori-.the enclosure tof the endof `said wire i withina sheath of insulation, thereby avoid- Y. ing jlekagelossesffrom the angular edge of; theendof therrvire; which facilitates ythe securing of the antenna wire; and which "'fprnvides means lfor safegnarding the insulation'f-romlateral strains thatV mayy arise fremswfaying of .they antenna in the wind.

Otherobjects of the invention will 'be disclosed-.asithe following description of the preferred embodiment thereof develops.

`inthe drawingsz- 'f Figure 1 isa 'longitudinal section through an. insulatorV keinbndying myl invention.

- Eiga-1re .Zisa Icross section taken along the is a cross section taken along the line-.OBTB .0f` Figurel;

Figure. 4 is across sectional f view of a mdiiied form of disk.. A

' Figure i'sxa longitudinal section through anfrilllsullltor,embodying my invention in a Slightly-modified lforin, means being provided afQl-.-an integral lead-in.

-Figure 6I is .a similar view of the. insulatorliQithait shownjin Figure 4, arranged for lie rrithaut the lead-in.

"Eigurel is a ycross section' taken along the -iBeferring now in detail yto the several liiguresythenumeral lrepresents an insulatf i withan integral skirt `or sheath 4l, the latter being of general cylindrical form and adapteqwtsurround thelterminal portion of the antenna wire. vThe reference character 5 representstheantenna wire which extends.

withinfthe yskirt or sheath of the insulating element 4and is secured to the latter by y 4 being runthrough theeye 7 formed in a boss i 8, whichfvprojects into the chamber within said skirt. Y l v It be apparent-'thatone of the chief objects of the skirt is to provide a long leakage path between the antenna wire and the exposure Ito rain or other atmospheric moisture. vThe outer end ofthe insulating elenient is preferably formed with an abrupt Hare t0 assist in draining away moisture freni the open end of the ski-rt.

It is essential to the ,efficiency of the insulator that the interior wall of the chainber within the skirt be kept free from a deposit of dust, which, due to its hygroscopic nature, reduces the dielectric density of the leakage path. A closure for said chamber therefore becomes essential, which I have provided in the form of a disk 9 of mica, a. phenolic condensation product, or other suitable insulating substance, perforated in the center as indicated at l() in Figure 1 and strung upon the antenna Wire'before. the latter vis attached to Athe insulating element. In that form of the invention illustrated in Figure l the interior of the skirt ofthe insulating` element is slightly tapered in a direction away from its `open end, in the manner shown at l1 and the disk 10 is of such size as to jam against said tapered Wall at a poi-nt slightly inside the riiaredv end of the insulating element, ythereby not only effectively sealing the chamber within the skirt against ingressl of dust but also excluding frost and moisture. The taper' vof the skirt is of that gradual. degree known as a sticking taper, so that the rdisk isfrictionally reta-ined in place and will not become dislodged by swaying of the antenna. Although the radius of the disk 9 is less in length 4than the length of the leakage path afiorded by the surface within the skirt of the insulating element, yet the substantially vertical disposition of the disk ensures the surface thereof against the collection of a or sharp edges of conductors. By having the wound portion 12 of the end of the antenna wire enclosed within a chamber having nonsconductive Walls, leakage from the corrugated contour thereof is substantially eliminated.

It Will be noted that the eyes 2 and 4 are relatively close, so that if the antenna wire is hung slack, an arcuate movement of the eye 7 about the eye 2 may take place due to stretching or sagging of the antenna wire as it sways in the wind. vWere it not tor the disk 9 this would cause an arcuate movement of the open end of the insulating element of considerable amplitude, bringing it into contact with the antenna wire, possibly with disastrous results to the skirt of the insulating element, but the disk 9 acts as a spacer, holding the antenna wire at all times out ot contact with, the insulating element.

It is contemplated-to make the insulating element of glass, porcelain or other suitable nonconductive substance, but when making it of baked ceramic material, manufacturing diiiiculties may arise, due to warping of the skirt during the baking process, so that it may be round desirable to dispense with the sticking taper of the interior wall of the skirt, as a means for holding the disk 9 in place and to make the skirt cylindrical inside as well as on the outside. The disk 9 may then be provided with a soft rubber thimble 12 at its center as shown in Figure 4 which trictionally engages the antenna wire. The disk, in this instance should have an easy lit within the skirt, so that it can be pushed into the skirt chamber as far as may be desired without hindrance from any slight inequalities in the shape of the wall of the skirt.

Figures 5, 6 and 7 illustrate a moditication of the invention which is equally adaptable for either end of the antenna where one end of the latter is integral with the leadin77 wire. In this form of the invention the insulating element remains the same as in the :first described form, but the insulation disk is made of'two disks, 13 and 14; fric tionally rotatable about the soft rubber thimble, and relatively to one another. The disks are provided with perforations 15 and 16 which register in one relative position o't said disks as shown in Figure 5, and are out of registry` in another relative position, as shown in Figures 6 and 7.

lhen the insulator is used at the remote end of the antenna, that is to say, the end remote from the lead-in7 the disks are placed in a position with the perforations out of registry, constituting an imperforate closure tor the skirt chamber. When it is desired to have a part of the antenna wire pass out of the skirt chamber, as an integral lead-in, the disks are arranged with the apertures 15 and 16 in registry, forming a single passage 1.7, Figure 5, through whlch the lead-in wire 18 may pass the latter being extended to any desired point outside the insulator. It is to be understood that when the antenna wire is being manipulated to secure it to the insulator the disk 9, in Figure 1, or the disks 13 and 14 in Figures 5 and 6, as the case may be, are pushed out along the antenna a sutiicient distance to be out of the way.

While I have now described a form of the invention which may be regarded as elemental in its simplicity it is to be understood that variations in the practical emiodiment of the same may from time to time be made to suit the exigencies of use without transcending the scope ot' the invention.

Having described my invention what I claim as new and desire to secure by Letters Patent, is

1. In combination with a conductor, an insulating element provided with a skirt forming a chamber surrounding a portion of said conductor, said insulating element having an eye within said chamber for the attachment oit said conductor and an external eye for the support of said insulating element, and an insulating piece slidable upon said conductor to a final position within the skirt of said insulating element, forming a closure for said skirt chamber.

2. An insulator comprising an insulating element adapted to form a dielectric link between a suspended conductor and a su port, said insulating element being provide with a skirt forming a chamber adapted to surround a portion of said conductor, and a disk of insulation material constructed to frictionally engage said conductor and to be slidably moved thereupon, said disk forming a closure for said skirt chamber when moved to a position Within the open end of said skirt.

3. An insulator comprising an insulating element having a portion thereof adapted to be normally tensioned between a suspended conductor and a support, said insulating element being provided with an untensioned skirt forming a chamber adapted to surround a portion of said conductor, and a closure for the open end of said chamber comprising an insulating member adapted to be slidably mounted upon said conductor and movable to a closing position Within said skirt chamber.

4. An insulator comprising an insulating element having a portion thereof adapted to be normally tensioned between a suspended conductor and a support, said insulating element being provided with an untensioned skirt forming a chamber adapted to surround a portion of said conductor, and a closure tor the open end of said chamber comprising an insulating member adapted to frictionally engage said conductor and to be slidably movable thereupon to and from a if closing position with respect to said skirt chamber.

f y5. An insulator comprising an insulating v element having a portion thereof adapted to be vnormally tensioned kbetween a suspended vconductor and a support, said insulating element being provided With an untensioned skirt forming a chamber adapted to sur- Y round, a portion of saidv conductor, and a y, closure for the open endofsaid chamber,

AMos FLOYD CURTRIGHT. 

